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v3.25.2

Borrowings - Additional information (Details) $ in Millions |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Feb. 24, 2020 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2025 USD ($) item | Dec. 31, 2024 USD ($)
Borrowings |  |  |  |
Number of customers having secured balances exceeding specified percentage of stockholders equity | item |  |  | 0 |
Threshold percentage of stockholders' equity |  |  | 10.00% |
Borrowings at FHLBC as percentage of total assets |  |  | 35.00% |
FHLBC stock |  |  | $ 4.2 | $ 4.5
Proceeds from term note | $ 30.0 |  |  |
Outstanding, net of deferred issuance costs |  |  | 59.5 | 59.5
Asset Pledged as Collateral with Right | Securities sold under repurchase agreements |  |  |  |
Borrowings |  |  |  |
Investment securities pledged with financial institutions, dollars |  |  | 73.7 | 73.6
Securities sold under repurchase agreements |  |  |  |
Borrowings |  |  |  |
Investment securities pledged with financial institutions, dollars |  |  | $ 47.3 | 36.7
Federal Home Loan Bank Advances |  |  |  |
Borrowings |  |  |  |
Borrowings at FHLBC as percentage of book value of certain mortgage loans |  |  | 60.00% |
FHLBC advance amount |  |  | $ 0.0 | $ 20.0
FHLBC stock |  |  | 4.2 |
Principal balance of loans collateralized |  |  | 1,330.0 |
Amount available for additional borrowings |  |  | $ 863.5 |
Subordinated Notes Due 2031 |  |  |  |
Borrowings |  |  |  |
Interest rate (as a percent) |  | 3.50% |  |
Basis points added to reference rate (as a percent) |  | 2.73% |  |
Face amount |  | $ 60.0 |  |

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